The result of this fight would mostly depend on which incarnation of the hulk Hellboy is fighting. If it's smart 'Bruce Banner' Hulk, then I'd actually root for Hellboy, because Hulk lost a lot of his strength when he was intellegent and let go of his rage.

Hulk is a disgraceful character with a pathetic backstory and no personality. He's no hero. Marvel would be better off writing the worthless bumbler off... or selling him to Green Giant.Red'll pull it off... even if it means calling in a telepath to have some fun w/ Hulk's lack of self-control.